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The fix for PR ld/22263 causes TLS relocations using ADRP to be relaxed into MOVZ, however this causes issues for the erratum code. The erratum code scans the input sections looking for ADRP instructions and notes their location in the stream. It then later tries to find them again in order to generate the linker stubs. Due to the relaxation it instead finds a MOVZ and hard aborts. Since this relaxation is a valid one, and in which case the erratum no longer applies, it shouldn't abort but instead just continue. This changes the TLS relaxation code such that when it finds an ADRP and it relaxes it, it removes the erratum entry from the work list by changing the stub type into none so the stub is ignored. The entry is not actually removed as removal is a more expensive operation and we have already allocated the memory anyway. The clearing is done for IE->LE and GD->LE relaxations, and a testcase is added for the IE case. The GD case I believe to be impossible to get together with the erratum sequence due to the required BL which would break the sequence. However to cover all basis I have added the guard there as well. build on native hardware and regtested on aarch64-none-elf, aarch64-none-elf (32 bit host), aarch64-none-linux-gnu, aarch64-none-linux-gnu (32 bit host) Cross-compiled and regtested on aarch64-none-linux-gnu, aarch64_be-none-linux-gnu Testcase in PR23940 tested and works as expected now and benchmarks ran on A53 showing no regressions and no issues. bfd/ChangeLog: PR ld/23904 * elfnn-aarch64.c (_bfd_aarch64_adrp_p): Use existing constants. (_bfd_aarch64_erratum_843419_branch_to_stub): Use _bfd_aarch64_adrp_p. (struct erratum_835769_branch_to_stub_clear_data): New. (_bfd_aarch64_erratum_843419_clear_stub): New. (clear_erratum_843419_entry): New. (elfNN_aarch64_tls_relax): Use it. (elfNN_aarch64_relocate_section): Pass input_section. (aarch64_map_one_stub): Handle branch type none as valid. ld/ChangeLog: PR ld/23904 * testsuite/ld-aarch64/aarch64-elf.exp: Add erratum843419_tls_ie. * testsuite/ld-aarch64/erratum843419_tls_ie.d: New test. * testsuite/ld-aarch64/erratum843419_tls_ie.s: New test. |
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config.in | ||
configure | ||
configure.ac | ||
configure.host | ||
configure.tgt | ||
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dep-in.sed | ||
elf-hints-local.h | ||
fdl.texi | ||
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genscripts.sh | ||
h8-doc.texi | ||
ld.h | ||
ld.texi | ||
ldbuildid.c | ||
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ldcref.c | ||
ldctor.c | ||
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ldfile.c | ||
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ldgram.y | ||
ldint.texi | ||
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pep-dll.c | ||
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TODO |
README for LD
This is the GNU linker. It is distributed with other "binary
utilities" which should be in ../binutils. See ../binutils/README for
more general notes, including where to send bug reports.
There are many features of the linker:
* The linker uses a Binary File Descriptor library (../bfd)
that it uses to read and write object files. This helps
insulate the linker itself from the format of object files.
* The linker supports a number of different object file
formats. It can even handle multiple formats at once:
Read two input formats and write a third.
* The linker can be configured for cross-linking.
* The linker supports a control language.
* There is a user manual (ld.texi), as well as the
beginnings of an internals manual (ldint.texi).
Installation
============
See ../binutils/README.
If you want to make a cross-linker, you may want to specify
a different search path of -lfoo libraries than the default.
You can do this by setting the LIB_PATH variable in ./Makefile
or using the --with-lib-path configure switch.
To build just the linker, make the target all-ld from the top level
directory (one directory above this one).
Porting to a new target
=======================
See the ldint.texi manual.
Reporting bugs etc
===========================
See ../binutils/README.
Known problems
==============
The Solaris linker normally exports all dynamic symbols from an
executable. The GNU linker does not do this by default. This is
because the GNU linker tries to present the same interface for all
similar targets (in this case, all native ELF targets). This does not
matter for normal programs, but it can make a difference for programs
which try to dlopen an executable, such as PERL or Tcl. You can make
the GNU linker export all dynamic symbols with the -E or
--export-dynamic command line option.
HP/UX 9.01 has a shell bug that causes the linker scripts to be
generated incorrectly. The symptom of this appears to be "fatal error
- scanner input buffer overflow" error messages. There are various
workarounds to this:
* Build and install bash, and build with "make SHELL=bash".
* Update to a version of HP/UX with a working shell (e.g., 9.05).
* Replace "(. ${srcdir}/scripttempl/${SCRIPT_NAME}.sc)" in
genscripts.sh with "sh ${srcdir}..." (no parens) and make sure the
emulparams script used exports any shell variables it sets.
Copyright (C) 2012-2018 Free Software Foundation, Inc.
Copying and distribution of this file, with or without modification,
are permitted in any medium without royalty provided the copyright
notice and this notice are preserved.